1. Field of the Invention
The present invention relates to an information processing apparatus on which a printer driver can be installed and a network system including the information processing apparatus.
2. Description of the Related Art
In recent years, information processing systems in which a host computer and a printer are connected over an interface, such as a Centronics interface, or a network, such as an Ethernet®, to perform printing have been commonly used. Typically, in such an information processing system, the printer analyzes print data input from the host computer, decompresses the print data into bitmap data, which represents an actual print image, and prints the image based on the bitmap data.
Typically, the host computer has a program (i.e., a printer driver) that is capable of performing more detailed control by receiving a drawing command from an application, converting the drawing command into print data, and outputting the print data.
Typically, the printer driver is distributed in the form of a file group (i.e., an install set) containing a plurality of program files and data files and is installed onto the host computer under the control of an operating system pre-installed on the host computer. That is, during installation of the printer driver, under the control of the operating system, a user or the install program copies the install set containing the printer driver and registers information regarding the printer driver to the operating system.
In addition, a more advanced information processing system in which with a host computer serving as a printer server connected to a printer, a client computer connected to the host computer through a network can perform printing using the printer has been researched, developed, and put to practical use.
In such an environment, the client must install the same printer driver as the printer driver installed on the printer server. As a program for facilitating such installation at the client, for example, Point & Print® of Microsoft Corporation has been know. In the function of Point & Print®, when a shared printer at a server side is selected and specified using an API of a client, the printer server receives information regarding the functions of the printer and the operating system of the client, selects a printer driver based on the received information, and transfers the printer driver to the client. The client then installs the printer driver transferred from the printer server.
The Point & Print® function is implemented as a part of operating systems available from Microsoft Corporation and offers some advantages. Specifically, a corresponding printer driver can be automatically installed, immediately when a user who operates the client computer wishes to perform printing. Also, the client can install a printer driver without a need for a storage media, such as a CD-ROM, on which the printer driver is stored.
Conventionally, an invention for a system in which a plurality of plug-in modules can be freely added to or removed from a base program has been proposed. A printer driver that runs under the control of a print service incorporated into an operating system can be regarded as one type of plug-in module for the print service. A method for adding or removing a plug-in module, containing a program and a data file, to or from an installed printer driver has not been contemplated. That is, while the operating system can recognize a printer driver that is under the control of the operating system, the operating system cannot dynamically recognize addition, removal, or change of a plug-in module that has been plugged into a printer driver and that is under the control of the operating system.
Also, for a case in which a module that a user wishes to add to a printer driver is already downloaded on a client computer, a method for additionally installing a desired module to a printer driver on the client computer or uninstalling the module from the printer driver has not been proposed. That is, a scheme for exchange printer-driver configuration information between the client and the server is not available during the printer-driver installation based on Point & Print®. Thus, even when a plug-in module is added to the server, module installation that additionally installs only a printer driver module added to the server cannot be performed so as to provide compatibility for a printer to be shared by the server and the client.